1. FIELD OF THE INVENTION
The present invention is directed to an electrical with a device for the protection thereof against overheating.
2. DESCRIPTION OF THE PRIOR ART
Devices for protecting electrical devices against overheating are known in the art. Such devices are disclosed by DE 23 42 015 A1.
For example, in refrigerator cooling units, a so-called motor start-up PTC thermistor can be connected in front of the units' electric motors, such that the drive shafts of the electric motors connect to the units' cooling compressors. In each start-up phase of an electric motor, the current flowing through the PTC thermistor heats it very strongly, as a result of which the resistance of the PTC thermistor increases within a very short time, frequently within seconds, from a few ohms in the cold state to very high resistances.
Since the surroundings of motor start-up thermistors contain oil residues or a generally oily atmosphere, there is a risk that these residues may under unfavorable circumstances be ignited. In the worst case, this may lead to the onset of a smouldering fire in the vicinity of the refrigerator cooling unit to which a motor start-up PTC thermistor is assigned.